rust/tests/ui/object-safety/object-safety-no-static.object_safe_for_dispatch.stderr
2023-01-11 09:32:08 +00:00

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error[E0038]: the trait `Foo` cannot be made into an object
--> $DIR/object-safety-no-static.rs:22:27
|
LL | let b: Box<dyn Foo> = Box::new(Bar);
| ^^^^^^^^^^^^^ `Foo` cannot be made into an object
|
note: for a trait to be "object safe" it needs to allow building a vtable to allow the call to be resolvable dynamically; for more information visit <https://doc.rust-lang.org/reference/items/traits.html#object-safety>
--> $DIR/object-safety-no-static.rs:9:8
|
LL | trait Foo {
| --- this trait cannot be made into an object...
LL | fn foo() {}
| ^^^ ...because associated function `foo` has no `self` parameter
= note: required for `Box<Bar>` to implement `CoerceUnsized<Box<dyn Foo>>`
= note: required by cast to type `Box<dyn Foo>`
help: consider turning `foo` into a method by giving it a `&self` argument
|
LL | fn foo(&self) {}
| +++++
help: alternatively, consider constraining `foo` so it does not apply to trait objects
|
LL | fn foo() where Self: Sized {}
| +++++++++++++++++
error: aborting due to previous error
For more information about this error, try `rustc --explain E0038`.